HA OS V7.6 Update to V8... fails

I have some troubles, updating HA OS V7.6 to a newer version.
HA is running on a 500GB SSD

While trying to find out the problem I started from 0

  • a fresh install on the SSD with V8.2 failed.
  • chkdsk on the SSD completed without errors.
  • installing V7.6 on the SSD was no problem.
  • installing V8.2 on a SD-card was also no problem.

Why is V8.2 working on SD but not on my SSD?
Any clue?